68 
My observations covered a period of ninety days from December 1, 
1885, and included a range of temperature from zero to 65° F. The 
hives were placed in a dark apartment, and an oil stove with a radiator 
was used for heating. Different degrees of temperature were maintained 
for several consecutive hours, and, as occasion required, for consecutive 
days, and careful observations were taken. 
At a range of temperature from 48° to 52° F., according to the humid- 
ity of the atmosphere in the cellar, bees, according to a rule of nature, 
enter into the hibernating state. After repeated trials over a wide 
range of temperature, at 41° F. I found the shape of the cluster most 
permanent. While that degree of temperature was maintained, little 
change in the shape or location of the clusters could be seen, and fune- 
tional activity on the part of individual bees, and of the whole colony 
as well, seemed to have reached the minimum degree of manifestation, 
even respiration seemed to be suspended. The change in the form of 
the cluster was determined by outline drawings on paper. The colonies 
presented substantially the same outline for days together when a uni- 
form temperature of 41° was maintained. I placed some colonies in a 
darkened building late in the fall of the year, and when the temperature 
was 40° F. natural heat on a dry day above ground, the same phenom- 
ena were observed. 
The temperature of the cellar was lowered by admitting the air through 
an outer room, so that no perceptible currents entered the apartment 
where the bees were kept. The degree of unrest and activity increased 
in proportion as the temperature neared the zero point. Thirty-seven 
degrees F. in a very dry cellar is a danger point, the danger increasing 
in proportion as the temperature is lowered or the humidity of the at- 
mosphere is increased. 
The degree of activity shown by bees when the temperature in the 
repository or cellar is 44° F. is not much greater than at 41°, all other 
conditions being the same. 
At intervals of about one week the bees arouse to activity, the form 
of the cluster changes, and after three or four hours of cheerful and 
contented humming, having in the mean time appeased their hunger, the 
cluster is reformed into a compact body, the. humming ceases, respira- 
tion becomes slow, profound silence reigns in the hive until change of 
temperature or the demands of hunger rouse the bees from the coma 
in which they have been bound. The more perfect the conditions for 
hibernation the longer the periods of inactivity. 
As the activity of bees is not much greater when the temperature 
in the cellar or repository is steadily maintained at 44 degrees than it 
is at 41 degrees, and as 41 degrees is too near the danger point, I find 
it safer to keep the temperature in dry winter repositories, whether 
above or below ground, at 44° F., and I find it better that the variation 
from the standard degree of 41° F. should be in proportion of 2 degrees 
above rather than 1 degree below. If the repository be damp a degree 
